Most of the current refrigerating and energy storing apparatuses and air conditioners utilize a compressor for cycle refrigerating the working substance through compression-expansion. It has the drawbacks of high product energy consumption, high operating cost, unstable operation, complicated maintenance, use of harmful medium, direct and indirect discharge of greenhouse gases and other contamination, noise pollution, strong dependence on electric power, and strong influence on electric power peak load.
The published specification of the Chinese a patent application for invention No. 91101569.8 discloses a refrigerating device composed of air conduit, coolant, transfusion box and cold storing body, wherein the air conduit exchanges heat with the coolant through the transfusion box for coolant, and the transfusion box for coolant exchanges heat with the cold storing body by communicating the coolant in steel tubes. In winter, it automatically introduce the amount of cold in the atmosphere by utilizing the static pressure difference generated by the hot and cold air and wind velocity in the air conduit, and store it in the cold storing body by using latent heat of phase change of water. When refrigerating in summer, the cold energy can be released through the heat exchange by the cold water supplying tube and the circulating of coolant with the cold storing body.
Said energy storage apparatus utilizes natural cold energy to achieve the object of energy saving and preventing the discharge of greenhouse gases and other contamination. But it has the following defects: (1) the input and output of cold energy is carried out by a large amount of commercial coolant, thus forced circulation is required at least for the output of cold energy, resulting in the low efficiency of the natural convection; (2) the input and output of cold energy both go through a secondary heat exchange, which will lower the efficiency of heat exchange and increase the loss of cold energy; (3) the air conduit can not eliminate loss of cold energy during conduction and convection; (4) the air conduit would be clogged; (5) the air and the steel tube wall have low efficiency of heat exchange, and a large amount of tubing and supports are required in real engineering; (6) the natural cold energy storage device satisfying the requirement of heat preservation, anti-expansion, anti-infiltration, and high efficiency of heat exchange is expensive, which is difficult to be put into practice.
Some of the current cold storing devices also use a single heat tube shown in FIG. 1 as the cold conducting element, but such storage apparatus with single heat tube still has the following defects: (1) the ascending vapor and descending coolant are in the same tube with circulation resistance occurred therebetween, causing an effect of heat exchange between each other, thus affecting the conducting power. Therefore the single heat tube has small cold conducting power; (2) relatively higher manufacturing cost under the condition of same conducting power; (3) the assembling is limited by angle; (4) it can not achieve ordered freezing by switching on and off or adjusting the magnitude of power.